If all the virtual machines on an ESXi host belong in the same zone, should you install VM-Series? If so, why?

Installing VM-Series on an ESXi host where all virtual machines (VMs) belong to the same zone is a prudent decision for several reasons, particularly highlighted in the correct response. One of the key concerns in network security is the potential for lateral movement of threats, even within a single zone.

Even if the VMs are currently operating in the same zone, having a firewall solution like VM-Series can help monitor, log, and control traffic between these VMs. This becomes crucial in scenarios where you might have internal threats, such as malware that spreads across machines within the same zone. Enforcing network security policies and traffic restrictions can prevent harmful activities, such as the transfer of malware, which could otherwise indicate a deeper compromise within the network. This proactive approach to securing all communications can help maintain the integrity and security posture of the data center.

Furthermore, the visibility provided by VM-Series can assist in identifying potentially malicious behavior early on, which is protective of the entire infrastructure. Thus, the reasoning behind employing a VM-Series firewall extends beyond current operational structures and addresses broader security needs.